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Factors predicting bacterial involvement in severe acute exacerbations of chronic obstructive pulmonary disease

Saad Nseir1, Béatrice Cavestri, Christophe Di Pompeo

  • 1Intensive Care Unit, Calmette Hospital, University Hospital of Lille, Lille, France. s-nseir@chru-lille.fr

Respiration; International Review of Thoracic Diseases
|June 13, 2008
PubMed
Abstract

Insights

Identifying bacterial infections in severe chronic obstructive pulmonary disease (COPD) exacerbations is crucial. A positive Gram stain and procalcitonin (PCT) levels over 0.5 ng/ml effectively predict bacterial isolation in these intensive care unit patients.

Area of Science:

  • Critical Care Medicine
  • Pulmonology
  • Infectious Disease

Background:

  • Reducing antibiotic use in intensive care units (ICUs) is essential.
  • Bacterial etiology is identified in only half of severe chronic obstructive pulmonary disease (COPD) exacerbations requiring antibiotic treatment.

Purpose of the Study:

  • To identify factors predicting bacterial isolation in severe acute exacerbations of COPD.
  • To aid in developing strategies for judicious antibiotic use in COPD patients.

Main Methods:

  • Prospective observational cohort study of 98 severe acute COPD exacerbations requiring mechanical ventilation.
  • Collected data on endotracheal aspirate purulence, hyperthermia, leukocyte count, C-reactive protein, and procalcitonin (PCT).
  • Performed Gram stain and quantitative endotracheal aspirate culture.

Main Results:

  • Bacterial isolation occurred in 40 exacerbations (41%).
  • Streptococcus pneumoniae, methicillin-sensitive Staphylococcus aureus, and Hemophilus influenzae were most common.
  • Positive Gram stain and PCT >0.5 ng/ml were independently associated with bacterial isolation, with a negative predictive value >95%.

Conclusions:

  • Positive Gram stain and PCT >0.5 ng/ml are reliable indicators of bacterial isolation in severe acute COPD exacerbations.
  • These findings support targeted antibiotic therapy and antibiotic reduction strategies in COPD management.

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